Internet and Computer Security Glossary
- Ad Blocker (or Ad Killer)
A program that helps to prevent unsolicited windows from appearing on your screen; these windows usually contain advertisements. - Adware
This refers to any software package which automatically plays, displays, or downloads advertisements to a computer after the software is installed, or while it is being used. While not necessarily malware, it can also be spyware. - Antispam
Software or a service to help prevent unsolicited mail and to complicate a spammer's method of collecting email addresses. - Antivirus (program/software)
A computer program that identifies and removes malicious software, such as viruses, worms, rootkits, trojan horses and other malware. - Back Door
A hole in the security of a computer system deliberately left in place by designers or maintainers. This can sometimes be exploited by hackers. - Brute Force Attack
A hacking method of defeating a login by trying a large number of password possibilities. This is why you should always use a strong password. You can use our Password Generator to create such a password. - Bug
An unwanted and unintended property of a program or piece of hardware, especially one that causes it to malfunction. - Click-reload
A popup that opens when you click on a link which at the same times reloads the page you are viewing. - Computer Worm
A self-reproducing program which is distinguished from a virus by copying itself without being attached to a program file, or which spreads over computer networks, particularly via email. - Cracking
The act of breaking into a computer system. - Cyberspace
Describes the world of connected computers and the society that gathers around them. Commonly known as the "Internet". - Denial of Service
Action(s) which prevent any part of a computer from functioning in accordance with its intended purpose. - Email Worm
A self-reproducing program which is distinguished from a virus by copying itself without being attached to a program file, or which spreads over computer networks, particularly via email. - Firewall
A system or combination of systems (gateway) that limits access between networks in accordance with a security policy. This can usually take the form of a hardware and/or software firewall. - Hacker
Usually someone with malicious intent who tries to learn more about someone's computer system and attempts to discover a computer users information through unauthorized intrusion. - Hacking
Unauthorized breach or attempted breach of a computer (system) by bypassing the security thereof. - Keystroke Monitoring
Software or hardware, (usually surreptitiously) installed on a computer to record every keystroke of the user. This creates a record of everything that was typed and done on the computer and can be used by a hacker for his devious purposes. - Launch-close
Popups that open when you click on a link which at the same time closes the page being viewed. Since the popup opens at the same time the main window is closed, your popup blocker may incorrectly interpret it as a "unload" popup window. - Letterbomb
A piece of e-mail containing live data intended to do malicious things to the recipient's machine or terminal. - Mailbomb
The mail sent to urge others to send massive amounts of e-mail to a single system or person, with the intent to crash the recipient's system. Mailbombing is widely regarded as a serious offense. - Malicious Code
Hardware, software, of firmware that is intentionally included in a system for an unauthorized purpose; e.g. a Trojan horse. Basically, software designed to infiltrate or damage a computer system without the owner's informed consent. - Malware
A generic term increasingly being used to describe any form of malicious software; e.g., viruses, trojan horses, malicious active content, etc. - Net Send Spam
Windows messenger vulnerability also known as net send spam, messenger spam or winpopup. These types of ads usually take the form of a gray pop up box bearing spam (unsolicited advertisements) with an "OK" button. - Network
Two or more machines interconnected for communications. - PGP (Pretty Good Privacy)
A freeware program primarily for secure electronic mail. - Phage
A program that modifies other programs or databases in unauthorized ways; especially one that propagates a virus or Trojan horse. - Phishing
The attempt to acquire sensitive information such as usernames, passwords and credit card details, by masquerading as a trustworthy entity in an email. - Phracker
An individual who combines phone phreaking with computer hacking. - Phreaking
The art and science of cracking the phone network. - Popup Blocker
A program that helps to prevent unsolicited windows from appearing on your screen; these windows usually contain advertisements. - Popup
A new browser window that appears (usually) unrequested by the user on the computer screen. It is most commonly used for advertisements. - Port Scan
A port scan is a series of messages sent by someone attempting to break into a computer to learn which computer network services, each associated with a "well-known" port number, the computer provides. - Probe
Any effort to gather information about a machine or its users for the apparent purpose of gaining unauthorized access to the system at a later date. - Proxy
A way to hide to the internet the IP address (and other data) of the user, by replacing his identity with that of the proxy (usually a website, but can be software too). - Ransomware
A type of malware that encrypts the user's computer data, and then demands a ransom for its restoration. - Replicator
Any program that reproduces copies of itself. - Retro-Virus
A virus that waits until all possible backup media are infected too, so that it is not possible to restore the system to an uninfected state. - Rootkit
A hacker tool that via a backdoor captures passwords and message traffic to and from a computer, and collects system and user information. This is a classic example of Trojan Horse software. - Router
An interconnection device that is similar to a bridge but serves packets or frames containing certain protocols. Routers link LANs at the network layer. - Scanner
A program which examines computers and network systems examining configurations and looking for security vulnerabilities. This type of program can be used by both defenders and attackers. - Sniffer
A program to capture data across a computer network, commonly used by hackers to capture user id names and passwords. - Social Engineering
The practice of obtaining confidential information by manipulating people into performing disclosure actions or divulging confidential information. - Spam
Usually unsolicited "junk" e-mail sent to large numbers of people to promote products or services. Sexually explicit unsolicited e-mail is called "porn spam." Also refers to inappropriate promotional or commercial postings to discussion groups or bulletin boards, as well as instant messaging spam, Usenet newsgroup spam, Web search engine spam, spam in blogs, wiki spam, mobile phone messaging spam and junk fax transmissions. - Spoofing
Pretending to be someone else or masquerading as a legitimate website. - Spyware
A general term for a program that surreptitiously takes partial control over the user's interaction with the computer, without the user's informed consent. It basically spies on you! - SSL (Secure Sockets Layer)
A session layer protocol that provides authentication and confidentiality to applications. - TCP/IP
Transmission Control Protocol/Internetwork Protocol. The suite of protocols the Internet is based on. - Trojan Horse
This term is derived from the well-known Greek epic of the Trojan Horse. It refers to an apparently useful and innocent computer program that surreptitiously performs malicious actions, such as the unauthorized collection, exploitation, falsification, or destruction of data. - Vaccine
Program that injects itself into an executable program to perform a signature check and warns if there have been any changes. - Virus
A program that can copy itself and infect a computer without permission or knowledge of the user. They almost always have bad intent and can damage your computer operating system severely. - Web Bug
A hidden link to another website, found on a webpage or in an email message, with the purpose of passing information (unbeknownst to the user) to said remote website. - Worm
A computer program that replicates from machine to machine across a network, usually without any user intervention. Unlike a virus, it does not need to attach itself to an existing program. A worm often clogs the network and consumes bandwidth as it spreads. - Zombie
software that turns your computer into an unwitting "zombie" that can be used by hackers for spam or attacks on other computers or networks.